CircleCI is upgrading the kernel version of the operating system that is used to run customer containers as part of the Docker executor on CircleCI. This change is critical to ensuring the underlying infrastructure that runs your jobs continues to provide reliable and performant execution. This upg…

Hi Sebastian! It seems like this upgrade hit our team recently and it caused some issues. In particular, we’re a Rails app using ActiveStorage and we’ve started getting ActiveStorage::IntegrityError failures on many of our tests that touch ActiveStorage. It seems there’s an issue with docker + cer…

@tgrathwell Thank you so much for the detailed report and for bringing this to our attention. We’re looking into ways to resolve this issue swiftly. The option we’re exploring involves expediting our schedule to upgrade the entire underlying OS to Ubuntu 20.04, which would include the 5.11 kernel …

To add to the googleability here: We suddenly started getting failed tests in CircleCI (but not locally) where the “Prawn” Ruby library failed to render images stored on disk using the “CarrierWave” library. CircleCI support suggested the issue could be due to this upgrade. The errors were specif…

This upgrade and the upgrade of the underlying operating system described in this post: Upgrading the underlying operating system for the Docker executor - 18.04 to 20.04 are now complete. The upgrade to the underlying OS included an upgrade of the kernel from 5.4 to 5.11. You can view the kernel …

Thanks, @sebastian-lerner . I removed our workaround and CI is still happy, so the upgrade appears to have fixed our issue :+1:

[image] sebastian-lerner: If you are experiencing issues with the new kernel and/or OS, please comment below. Details on performance improvements seen with this latest OS upgrade can be seen here .

Upgrading the underlying kernel for the Docker executor

Announcements

sebastian-lerner December 16, 2021, 3:50pm 7

Details on performance improvements seen with this latest OS upgrade can be seen here.

Topic		Replies	Views
Upgrading the underlying operating system for the Docker executor Announcements docker	13	2424	April 2, 2019
Upgrading the underlying operating system for the Docker executor - 18.04 to 20.04 Build Environment	2	2867	December 16, 2021
Notification of updates to ‘machine’ images for CircleCI 2.0 Announcements	0	1362	August 24, 2017
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Upgrading the underlying kernel for the Docker executor

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